The machining of the complex forms is a characteristic of moulds and matrices manufacturing. Owing to the fact that these forms became increasingly complicated, the production of moulds and matrices require tolerances which are particularly severe. One of the principal objectives to be reached is the precision of machining and the improvement of the micro geometrical state of machined surfaces, for the minimization of polishing operations after machining which still necessary to obtain a good finished part, which is required by the car industry and the aeronautic industry. To reach these goals, it is important to choose a tool which fulfils the requirements of a machining which could be carried out in various orientations. This will make possible the machining of complex forms by using a milling machine with several axes. Among the tools allowing the realization of these complex forms, there is the ball-end mill. The goal of this work is to study the geometry of the mill’s spherical part, in order to determine the contact zones between the part of complex form and the tool which is following a trajectory in space.

The world-wide crisis of water will make that the transboundary water resources will be the object of tensions and litigations increasingly marked. Also, the transboundary conflicts on fresh water intended to the categories of traditional uses are subjected to a growing attention on behalf of national and international organizations. Each case of conflict, related as well to surface water as groundwater, has its accurate characteristics and to appreciate its relative importance, it is necessary to consult a broad documentation based on reports of commissions, organizations or groups of research. According to criteria and data taken into account, the situation is some times appreciated differently.